Buyer got a refund when I sent them their item

I sell clothes and other things like that on places like depot and eBay to make a little extra money. I had a buyer reach out to me and asked to punches 2 belts and a hat for around $500 and asked to pay through PayPal. I looked into PayPal and everyone said it was a great way for buyers to not get scammed and seemed safe over all. They sent the $500 and I shipped the next day, color me surprised when I get an email that they opened a case with PayPal saying I scammed them and I sent them an empty box. I tried to work with PayPal but they refunded the buyer without any hesitation and now I'm out $500 and 2 belts and a hat. Is there anyway to get that money back or did the A hole get the belts and hat for free?